Step-by-step explanation:

18x³y⁴
a
Step-by-step explanation:
The LCD of the denominator is 12. For this one it is possible to just 'see' that 6 is a divisor of 12. When in doubt, you can always get an answer by just multiplying the denominators. (ie., you can turn 11/12 into 66/72 and 1/6 into 12/72).
In this case, the easiest is to convert 1/6 into 2/12. (multiply both numbers by 2).
Then it becomes:
Answer:
Water chlorination is the process of adding chlorine or chlorine compounds such as sodium hypochlorite to water. This method is used to kill certain bacteria and other microbes in tap water as chlorine is highly toxic to those microorganisms. Answer via google.
Step-by-step explanation:
Suppose x quarts of the 50% solution
0.5x+0.2*20=0.4(x+20)
0.5x+4=0.4x+8
0.1x=4
x=40